CloudEvent with no datacontenttype parsed as JSON instead of plain text

Describe the Bug Doing a demo based on this blog to consume S3 events from Kamelet The nodejs SDK can’t handle the HTTP POST request with cloud event Using the following code https://github.com/knative/docs/blob/main/docs/serving/samples/cloudevents/cloudevents-nodejs/index.js

Steps to Reproduce

1. create nodejs service
2. create trigger to send cloudevent from broker to nodejs service

Expected Behavior That the cloud event is properly handle. The knative event-display using the goland cloudevent can handle plaintext in body and missing content-type in header. https://github.com/knative/eventing/blob/main/cmd/event_display/main.go#L59

Additional context

Try both versions of the SDK 4.0.3 and 5.0.0 same error

The input event from Camel Kamelet S3 is the following

Debug Incoming Request: {
   "headers": {
     "host": "func1.default.svc.cluster.local",
     "user-agent": "Go-http-client/1.1",
     "content-length": "11",
     "accept-encoding": "gzip",
     "ce-id": "A8A6BD24B2AE5FF-0000000000000017",
     "ce-knativearrivaltime": "2021-11-17T22:48:50.315578709Z",
     "ce-source": "source",
     "ce-specversion": "1.0",
     "ce-time": "2021-11-17T22:48:50.306Z",
     "ce-type": "org.apache.camel.event",
     "forwarded": "for=10.131.0.156;proto=http",
     "k-proxy-request": "activator",
     "traceparent": "00-0f3421c775056be4f762f87b5cee145d-5f24409ef4edc327-00",
     "x-forwarded-for": "10.131.0.156, 10.128.2.48",
     "x-forwarded-proto": "http",
     "x-request-id": "13396d30-5487-46c1-9d21-b3fd675447e0"
   },
   "body": "test func1\n"
 }

The error is the following

SyntaxError: Unexpected token 
  in JSON at position 11
     at JSON.parse (<anonymous>)
     at parseJSON (/opt/app-root/src/node_modules/cloudevents/dist/parsers.js:39:67)
     at JSONParser.parse (/opt/app-root/src/node_modules/cloudevents/dist/parsers.js:40:16)
     at parseBinary (/opt/app-root/src/node_modules/cloudevents/dist/message/http/index.js:166:23)
     at Object.deserialize [as toEvent] (/opt/app-root/src/node_modules/cloudevents/dist/message/http/index.js:86:20)
     at /opt/app-root/src/index.js:70:24
     at Layer.handle [as handle_request] (/opt/app-root/src/node_modules/express/lib/router/layer.js:95:5)
     at next (/opt/app-root/src/node_modules/express/lib/router/route.js:137:13)
     at Route.dispatch (/opt/app-root/src/node_modules/express/lib/router/route.js:112:3)
     at Layer.handle [as handle_request] (/opt/app-root/src/node_modules/express/lib/router/layer.js:95:5)

cc @lance

[duglin]

Seems to me that the SDK should not be parsing the body at all - it’s binary and should be passed on to the app as an array of bytes. If there was a content-type header that says it is JSON, then the SDK might try to be smart and convert it to a JSON object, but w/o that it seems like the SDK has no choice but to treat it as an array of bytes, not JSON.

[lance]

Seems to me that the SDK should not be parsing the body at all - it’s binary and should be passed on to the app as an array of bytes.

I’ll be willing to bet this is what the Go SDK is doing.